Melt chocolate chips, milk and butter/margarine in a microwave safe bowl for one minute. Take out and blend together. If all of the chips don't melt, it's OK as the bottom of the bowl will be hot enough to melt them when you are stirring. You can add Pecan or Walnut chips, or two tablespoons of peanut butter.
Line a square pan with foil and spray with Pam. Spread into foil-lined pan and refrigerate for two (2) hours. On a plate, turn fudge upside down and pull off the foil. Cut into squares and serve. Place fudge into a plastic container and cover with lid.